Colored rubber product and process of preparing it



Patented May 21, 1935 umTEos rarEs PATENT OFFICE",

COLORED RUBBER PRODUCT AND PROC- ESS OF PREPARING IT Heinz Eichwede, Frankfort-bn-the-Main-Hochst, Germany, assignor to General Aniline Works,

Inc., New York, N. Y., rm

l No Drawing.

SerialNo. 703,488. In

1 6 Claims. (01. 18-50) a corporation of Dela- Application December 21, 1933,

Qermany December 23, l

acid-ethyl esterl The mixture is p a 'vulcanization press rm--12 at a pressure of 3 atmospheres above atmospheric pressure; There is obtained a clear red vulcanizate of very good fastness properties.

(2) A rubber mixture is prepared in the usual manner from crepe rubber, the usual admixtures and 1 to 2 parts of the disazo-dyestufi described in Example 1. The mixture is vulcanized by immersing it for Sseconds in a solution of 3 parts of sulfur chloride in 9'? parts of benzine. The shades and fastnessproperties of the coldyuloanizate, thus obtained, are similar to those of wherein the diphenyl radical and the' phenyl radical of the pyrazolone may be substituted by halogen, alkylior alkoxy groups and R stands for methyl or ethyl.

The manufacture of these disazo-dyestufis is disclosed in -my co-pending application Serial No. 703,489, filed December 21, 1933, for Waterinsoluble disazo-dystufis. V g a By reason of the saiddyestufis being practically insoluble in rubber, they do not bleed when the rubber products are worked up; 1 neither do they give rise to that phenomenon which is known as blushing oreffiorescencewhenthe rubber articlesare. stored. Furthermore, they arei in soluble in benzine which renders them especially suitable also for being used in connect on with cold vulcanization processes Whichare advantageously carried out in the presence of benzine."

The following examples will further illustrate the nature of this invention,-but the invention is not restricted to these examples. The parts are by weight: 1

(1) A rubber mixture is prepared from! 100 parts of crepe rubber, 1 part'of stearic acid,2.6 parts of sulfur, 5 parts of zinc white, 1 part of rnercapto-benzothiazol, p3 partof hexamethylenetetramine',60'parts of calcium carbonate, 0.6 part of ozocerite, 10, parts of lithopone, 5 parts of titanium dioxideandl t'2 parts of the disazodyestufi obtainable by coupling 1 mol of tetrazotized 3.3-dichloro-4.4-diamino-diphenyl with 2 mols of 1phenyl-5-pyrazolone-3-carboxylic the vulcanizate obtainable according to Example 1.

(3) A mixture is prepared from 100 parts of crepe rubber, 2.5 parts of sulfur, 0.35 part of thiuram, 5v parts of zinc white, 0.6 part 0t ozocerite, 0.5 part of stearic acid 2 parts oi the disazo-dyestufi obtainable by coupling tetra-pass diamino-diphenyl, with Lemmas-wine: 1one-3-carboxylic acid ethyl ester. 'I'lie vulcanized in an iron mould in a vuloaniza on press for minutes at a superatmosphricpressure of 2'atr'nospher'es.

obtained. V b p l p (4) A mixture is prepared from 3! crepe'rubber, 28 parts of 5mm, 0L4 part of par aifin oilg'3 parts of 'stearic acid, 2 parts of brown coal'tar oil, 2 parts of colophofiy, BO'part's' of car:

cium carbonate, 1315' parts of zinc white, 4 parts of magnesium oxide, 6 parts of calolin, 0.4 part of thiuram and 2 parts of the disazo-dyestufl obtainable by coupling tetrazoti'zed 3.3'-dimethoxylxi-diamino-diphenyl with l-phenyl- 5-pyrazolone-3-carboxylic acid-ethyl-ester. The mixture is vulcanized for 45 minutes in hot air at q and inthis way a violet-red vulcanizate is obtained. p

Bereplacing in theioregoinig examples stuiis :rnentioned' therein 1 by others which comprised by the general formula and have been prepared from tetrazo-compounds such as 3 .3 dime thyl-4 .4 -diaminodiphenyl, 3.3-dibromo-4.4'-diaminodiphenyl,

A red vulcanizate b 2.2 dichloro-3.3'-dimethyl-4.4 diaminophenyl,

2.2'-dichloro 5.5 dimethoxy-4.4'-diaminodiphenyl,

2. Colored rubber products containing a water-insoluble disazo-dyestufi of the following general formula:

3.3'-dichloro 2.2'-dimethoxy 4.4'-diaminodiphenyl or v 6.6 -dichloro-3.3'-diethoxy-4.4'-diaminodiphenyl and coupling components, such as 1- (Zfi-chlorophenyl) -5-,pyrazolone-3 carboxyl ic acid-methylor ethyl-ester,

"1 2'5 dichlorophenyl) -5-pyrazolone 3 carboxylic acid-methylor ethyl-ester,

1- (4'-methy1phenyl) -5-pyrazolone-3-carboxylic acid-methylor ethyl-ester,

1- (2 chloro-6'-methy11 ohz enyl) -5-pyrazolone-v 3-carboxylic acid-methylor ethyl-ester,

wherein the diphenyl radical and the phenyl radical of the pyrazolone may be substituted by halogen, alkyl or alkoxy groups and. R stands for methyl or ethyl.

3. Colored rubber products containing a water-insoluble disazo-dyestuff of the following general formula:

wherein the diphenyl radical and the phenyl radical of the pyrazolone may be substituted by halogen, alkyl or alkoxy groups.

4. Colored rubber products containing a water-insoluble disazo-dyestuif of the following general formula:

-5 pyrazolone-B-carboxylic acid-ethylr-ester,

- there are obtained rubber dyeings of shades and fas' tnes's' properties similarto those disclosed in the foregoing examples,

1 11.: The process of producing colored rubber products which comprises mixing a rubber prod,- uct with a water-insoluble disazo-dyestufi corresponding to the following general formula:

wherein the 'diphenyl radical and the phenyl radical of the pyrazolone may be substituted by halogen, alkyl or alkoXy groups and R stands for methyl or ethyl, and then vulcanizing the mixture. r

chloro-4.4-diamino-diphenyl and 1-phenyl-5- pyrazolone-3-carboxylic acid-ethyl-ester.

HEINZ EICHWEDE. 

